Earth-like might not be the best yardstick

I love all the stories about the search for water
and possibly life on Mars and the
new discoveries
of more earth-like extrasolar planets, but I just think
there's a bit of a perspective problem when it comes
to presuming that being closer to earth-like is better
when it comes to the search for life. Yes, the only known sample point
we have of life is that existing on our own planet (for now), but
that doesn't mean that our planet is optimal
for the formation or survival of life.

That's a real long time and not much progress
to show for it. We may not be living on a fertile world, an optimal
environment for life; maybe we live on the
galactic equivalent of a barren weed strewn city lot.

Heh, quite a good point. We have the potential to create a utopian and edenistic earth... but most people aren't concerned about it, don't know how, or haven't even thought about it.

We can desalinate landscape and put in forests structured for human use, but we don't: http://www.youtube.com/watch?v=sohI6vnWZmk

Hmm. Given that so far our explorations deeper into the earth keep revealing more extremophile bacteria, the estimate may be a bit low. There is evidence, for example, that many ore concentrations (like some iron ores) may be biological in origin.
At the very least, this suggests that quite a bit of the earth's crust at least passes through the planetary ecosystem on a regular basis (just like the atmosphere and ocean do) on long time scales, and is far from inert.